Nickel plating solutions



NICKEL PLATING SOLUTIONS Jack L. Towle, Cleveland, Ohio,

Chemical Company, Cleveland, Ohio No Drawing. Filed Feb. 10, 1960, Ser. No. 7,784 7 Claims. (Cl. 20449) assignor to The Harshaw Ohio, a corporation of This invention, which is a continuation-in-part of copending application Serial No. 833,398, filed August 13, 1959, now abandoned, relates to electrodeposition of bright nickel, that is to the production of bright deposits of nickel which are bright as taken from the electroplat ing solution without bufling or polishing of any kind, and to the composition of solutions suitable for the production of such deposits.

Various solutions are known which are capable of producing bright nickel deposits. Some of these are of commercial value. Some are superior in particular respects while being inferior in other respects. Brightness, resistance to corrosion, long periods of trouble-free operation, adherence, ductility, freedom from pits, streaks and other irregularities, resistance to impurities in the bath are some of the factors which the art seeks to find in high degree and as many as possible in one process.

I have now discovered a group of closely related classes of compounds which are excellent additives for use in acid nickel plating when used in connection with the aromatic sulfonates, sulfonamides and sulfimides. The latter may be referred to as control agents, the former as brighteners or auxiliary brighteners.

The class of brighteners with which the invention is concerned are those having the formula wherein R is a member selected from the group consisting of -H, --CN,

I radical selected from and W is a hydrocarbon radical and preferably a hydrocarbon radical having from 1 to 7 carbon atoms; X is an acid radical selected from the group consisting of sulfate, sulfonate, halide and perchlorate radicals; n is an integer from 1 to 6, and n is an integer from 1 to 6.

The classes of brighteners referred to are as follows: 8 (0112mm, W/ [\X where W is a hydrocarbon radical, X is an acidic radical selected from theg roup consisting of R is a hydrocarbon radical and n is an integer where from 1 to 2 inclusive.

where R is an alkyl group, W is a hydrocarbon radical, XX is an acidic radical selected from the group consisting of OSO OR', where R is a hydrocarbon radical where'R' is a hydrocarbon radical and n is an integer from 1 to 2 inclusive.

where W is a hydrocarbon radical, X is an acidic radical the group consisting of -OSO OR where R is a hydrocarbon radical, and n is an integer of from 1 to 2 inclusive. 7 V

Specific examples of brightener compositions according to the invention are set forth in Table I below:

Table I 1 Preferred Concen- No. Structure Name tration,

Grams per Liter 1 NC-GH:CHz-S-CHg-CHg-CN Ethyl bis (B-cyanoethyl) sulfonium 003-. 02

ethyl sulfate.

CgH5 OSOIOCQHB 2 NCCHrCHz-CH,CH CN Benzyl bis (B-cyanoethyl) sulfonium nos-.02

iodide. C r I 3 NCCH CH -CHCH,---SGHCH;CN 1,2ethylene-bis (B-cyanoethyl ethyl- 003. 02

sulfonium ethylsulfate) CaHs O"-SO2OC2H5 CnHr 0"-SO2O 02115 4 CHaCHzCHr-SCH2CH2CN B-cyanoethyl propylethylsulfonium 003-. 02

ethyl sulfate.

C2115 0-'SO2O ofl b 5 NC-CHzCHr-SCH2CHz-CN Methyl-bis (B-eyanoethyl) sulionium .003-.02 p-toluene sulfonate. CH9 O'SO:C CHa 6 CH3CHrCH SCHaCH=ON Ethylpropyl-B-cyanoethyl sulfonium 003-. 02

p-toluene sulfonate, 0,115 os-mO-orn The second addition agent, which cooperates with the brightener in bright, acid, nickel plating solutions falls into the category of organic sulfonamides, sulfirnides, and sulfonates.

ALL SULFATE NISO4.7H2O 100 to 400 grams, preferably 200 to 3 grams.

Boric acid 0 to 60 grams, preferably to 4-0 grams.

Wetting agent (eg.

The amount of control agent dlssolved 1n the acid 5 lauryl fate 8 a g gih P nickel plating solution ranges from .05 gram per liter to H2O to make 1000 ALL CHLORIDE grams per liter, best results being obtained from about N1C12'6H20 168 5 %0 mm. preferably 0 grams. 2 to about 5 grams per liter. These may be used 1n Boric acid 0 to 60 grams, preferably admixture as well as singly. That is, two control agents 10 10 to 40 grams- Wetting agent (e.g. sodium may be used instead of one, their combined concentralauryl sulfate) 0 to 0.5 gram, preferably tion being kept within the above indicated limits. H20 to make 1000 m to gram Table II AROMATIC SULFONAMIDES benzene monosulionamide OflHsO2NH2 saccharine, sodium salt OBHASOgCONNfi. -toluenesulionamide CHaCgHJSOQNHQ trichlorodibenzenesulfonamide. ClzOeHaSOzNHSOzCBILOl dl-B-naphthalenesulfonamido C oH7sO2NHSOzC1uH7 4-carboxydibenzenesnlfonamide OgI'l5SOgNHSO20uII4COOLI N ,N -bis (phenylsulfonyl)-t,4-diphenyldisulfonamide CuH5SOQNHSOzOflH4CuH4SO2NHSO2CoH5 p,p-0Xy-blS(dlbGIlZeHGSUlfOIlBIDldB) CaHsSO NHSOzOeI'lgOcaHi sogNHsozc/ofi a -methylene-bis (dibenzenesultonarnide) CuIIsSOQNHSO2G H4CH2CH4SOZNHSOQCqHs AROMATIO SULFONATES UNSATURATED ALIPHATIC SULFONAMIDES AND BULFONIC ACIDS sodium vinyl sulfonate-.. HzC=CHSO3Na sodium allyl sn1fonate H2U=CHCHzSO3NB vinyl sulfonam1de H C=CHS OZNHZ allyl sulfonamide H C=GH CHzS OzNHa The constituents of the plating bath, according to the preferred practice of the invention, are (1) water, (2) nickel sulfate, nickel chloride, or a mixture of nickel sulfate and nickel chloride, (3) the brightener, (4) a sulfonate, a sulfonarnide, a sulfimide, or one or more sulfonates, sulfonarnides, suh'imides or mixtures thereof of the type previously indicated, (5) and a wetting agent (optional). An additional ingredient of the solution which is desirable is a bufiering agent such as boric acid, formic acid, or the like.

it will be noted that in reference to the major constituent of the nickel plating solution, the solutions are similar 'to the well known all chloride, all sulfate, and sulfate-chloride or Watts type acid nickel plating solutions. The essential novel feature of the invention is the use of an acid nickel plating solution having one or more nickel electrolytes selected from nickel sulfate and nickel chloride and additionally containing cooperating brightening agents, one of which is at least one carrier selected from the group consisting of unsaturated aliphatic sulfonamides, unsaturated aliphatic sulfimides, unsaturated aliphatic sulfonates, aromatic sulfonamides, aromatic sulfimides and aromatic sulfonate-s, and the other of which is a small amount of a brightener of the type heretofore indicated.

The basic solutions in connection with which the bright ductile nickel deposits are realized when containing the cooperating addition agents dissolved therein are as follows:

SULFATE-CHLORIDE WATTS TYPE NisO4.7H2O ato 400 grams, preferably 200 to 300 grams. NiCl2.GH20 10 to 60 grams, preferably 25 to 40 grams. Boric acid 0 t9 50 grams, preferably 19 to 40 grams. Wetting agent (e.g. sodium lanryl sulfate) 0 0.5 gram,

All All Watts Sulfate Chloride pH Temperature, Cathode Current Density (amp,

In the preparation of the plating solution according to the invention, I add to each of the foregoing basic solutions a suitable quantity of the brightener and also one ormore of the unsaturated aliphatic, or aromatic sulfonamides, sulfimides, and sulfonates. The plating solution for the best results, contains an antipitting agent although the deposits may be suitable for some purposes Without eliminating pitting. Sodium lauryl sulfate or other wetting agents, such as the sodium sulfate derivative of 7-ethyl-2-methylundecanol-4 and the dihexyl ester of sodium sulfosuccinic acid may be used as an antipitting agent, although its use is not essential and other wetting agents or mixtures of Wetting agents may be used to control the pitting. Forsome purposes pitting may be tolerated and sometimes very little pitting occurs.

Specific examples of electroplating solutions containing difierent cooperating brighteners and carriers are illustrated in the following table designated as Table III. It should be understood that these specific electroplating solutions may be used with or without air agitation. The operating conditions for obtaining bright ductile nickel deposits are also set forth in the table. In each case a bright nickel deposit of from 0.05 to about 1 mil thick or thicker may be secured by electrolyzing the electroplating solution between an anode and a buffed brass cathode. Similar results may be secured on other types of cathodes conventionally employed in acid nickel plating processes utilizing solutions of the type indicated herein.

Table 111 Grams per liter NiSOA.7H20- 300 300 300 300 NlClz.6Hz 40 40 40 40 1131303 40 4O 4O 40 Sodium lauryl sulfate 0.15 0.15 0.15 0.15 l,2-cthylene-bis(B-cyanoethyl-ethylsulfonium ethylsuliate) 0.15 rnethyl-bis(B-cyanoethyll sulionium p-toluene sulfonate 0. 01 B-cyanoethyl propylethylsulfon in eth sulfate 0.01 Ethyl bis(B-eyanoethyl) sulionium ethyl sulfate 0.01 [CeklsSCzNl'lSC 11 11..-. 3 3 [CnH5SC2NHS( 2CH51 0 Current Density Temperature range F 140 140 What I claim is:

1. An aqueous acid nickel plating solution comprising a source of nickel ions selected from the class consisting of nickel sulfate, nickel chloride and mixtures thereof, said solution also containing cooperating additives for enhancing the brightness of nickel deposits produced therein, one of said additives being present in a concentration of (from 0.05 to 20 grams per liter and being chosen from the class consisting of aromatic sulfonates, aromatic sulfonamides, aromatic sulfimides, aliphatic sulfonamides and sulfonic acids, and the second being present in a concentration of from 0.0025 to 0.075 gram per liter and being chosen from the class of compounds having the formula wherein R is a member selected from the group consisting of H, -CN,

-S(CHa)nCN, onuonnn -s- W X W X W is a hydrocarbon radical; X is an acid radical selected from the group consisting of sulfate, sulfonate, halide and perchlorate radicals; n is an integer from 1 to 6 and n is an integer from 1 to 6.

2. An aqueous, acid, nickel plating solution comprising nickel plating solution comprising nickel sulfate and nickel chloride and cooperating additives being present in a concentration from 0.05 to 20 grams per liter and, one of said additives being chosen from the class consisting of aromatic sulfonates, aromatic sulfonamides, aromatic sulfimides, aliphatic sulfonamides and sulfonic acids and the other of said cooperating additives being a compound of the formula NC-CHa-CHa-S-CHs-CHn-C'N CgHz OBOzOCaHI and being dissolved in said solution in concentration from 0.0025 to 0.075 gram per liter.

3. An aqueous, acid, nickel plating solution comprising nickel plating solution comprising nickel sulfate and nickel chloride and cooperating additives, one of said additives being present in the concentration of from 0.05 to 20 grams per liter and being chosen from the class consisting of aromatic sulfonates, aromatic sulfonamides, aromatic sulfimides, aliphatic sulfonann'des and sulfonic acids and the other of said cooperating additives being a compound of the formula and being dissolved in said solution in concentration from 0.0025 to 0.075 gram per liter.

4. An aqueous, acid, nickel plating solution comprising nickel plating solution comprising nickel sulfate and nickel chloride and cooperating additives, one of said additives being present in a concentration of from 0.05 to 20 grams per liter and being chosen from the class consisting of aromatic sulfonates, aromatic snlfonarnides, aromatic sulfimides, aliphatic sulfonarnides and sulfonic acids and the other of said cooperating additives being a compound of the formula and being dissolved in said solution in concentration from 0.0025 to 0.075 gram per liter.

5. An aqueous, acid, nickel plating solution comprising nickel plating solution comprising nickel sulfate and nickel chloride and cooperating additives, one of said additives being present in a concentration of from 0.05 to 20 grams per liter and being chosen from the class consisting of aromatic sulfonates, aromatic sult'onarnides, aromatic sulfimides, aliphatic sulfonamides and sulfonic acids and the other of said cooperating additives being a compound of the formula and being dissolved in said solution in concentration from 0.0025 to 0.075 gram per liter.

6. An aqueous, acid, nickel plating solution comprising nickel plating solution comprising nickel sulfate and nickel chloride and cooperating additives, one of said additives being present in a concentration of from 0.05 to 20 grams per liter and being chosen from the class consisting of aromatic sulfonates, aromatic sulfonamides, aromatic sul fimides, aliphatic sulfonamides and sulfonic acids and the other of said cooperating additives being a compound of the formula NC-CHaCHz-S-CIhCHz-CN and being dissolved in said solution in concentration from 0.0025 to 0.075 gram per liter.

No references cited.

UNITED STATES PATENT OFFICE--- CERTIFICATION OF CORRECTION atent No. 2,972,571 February 21, 1961 Jack L. Towle It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, line 13, for "theg roup" read the group Column 2, line 23, for "QQQ" read line 341, strike out radical"; columns 1 and 2, Table 1, second column, under the heading "Structure", and opposite item No. 6', the formula should Appear as shown below instead of as in the patent:

C2H5/ o'-so Gon column 5 line 64 to column 6, line 2, claim 2 should appear as shown below instead ofas in the patent:

2. An aqueous, acid, nickel plating solution comprising nickel plating solution comprising nickel sulfate and nickel chloride and cooperating additives, one of said additives being present in a concentration from 0.05 to 20 grams per liter and being chosen from the class consisting of aromatic sulfonates, aromatic sulfonamides, aromatic sulfimides, aliphatic sulfonamides and sulfonic acids and the other of said cooperating additives being a compound of the formula NCCH CH SCH CH CN, and being C 14 OSO OC H dissolved in said solution in concentration from 0.0025 to 0.075 gram per liter.

Signed and sealed this 18th day of July 1961.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attcsting Officer Commissioner of Patents 

1. AN AQUEOUS ACID NICKEL PLATING SOLUTION COMPRISING A SOURCE OF NICKEL IONS SELECTED FROM THE CLASS CONSISTING OF NICKEL SULFATE, NICKEL CHLORIDE AND MIXTURES THEREOF, SAID SOLUTION ALSO CONTAINING COOPERATING ADDITIVES FOR ENHANCING THE BRIGHTNESS OF NICKEL DEPOSITS PRODUCED THEREIN, ONE OF SAID ADDITIVES BEING PRESENT IN A CONCENTRATION OF FROM 0.05 TO 20 GRAMS PER LITER AND BEING CHOSEN FROM THE CLASS CONSISTING OF AROMATIC SULFONATES, AROMATIC SULFONAMIDES, AROMATIC SULFIMIDES, ALIPHATIC SULFONAMIDES AND SULFONIC ACIDS, AND THE SECOND BEING PRESENT IN A CONCENTRATION OF FROM 0.0025 TO 0.075 GRAM PER LITER AND BEING CHOSEN FROM THE CLASS OF COMPOUNDS HAVING THE FORMULA 